INA281B2IDBVR

The INA281 is a high-precision current sense amplifier that can measure voltage drops across shunt resistors over a wide common-mode range from -4 V to 110 V. The negative common-mode voltage allows the device to operate below ground, thus accommodating precise measurement of recirculating currents in half-bridge applications. The combination of a low offset voltage, small gain error and high DC CMRR enables highly accurate current measurement. The INA281 is not only designed for DC current measurement, but also for high-speed applications (like fast overcurrent protection, for example) with a high bandwidth of 1.3 MHz and an 65-dB AC CMRR (at 50 kHz). The INA281 operates from a single 2.7-V to 20-V supply, drawing 1.5 mA of supply current. The INA281 is available with five gain options: 20 V/V, 50 V/V, 100 V/V, 200 V/V, and 500 V/V. These gain options address wide dynamic range for current-sensing applications. The INA281 is specified over an operating temperature range of -40 °C to +125 °C and is offered in a space-saving SOT-23 package with two pin-out variants.

Applications

• Active antenna system mMIMO (AAS)
• Macro remote radio unit (RRU)
• 48-V rack server
• 48-V merchant network & server power supply (PSU)
• Solenoid control
• Valve control
• Telecom equipment
• Power supplies

Key features

• Wide common-mode voltage: Operational voltage: -4 V to +110 V; Survival voltage: -20 V to +120 V
• Excellent CMRR: 120-dB DC CMRR; 65-dB AC CMRR at 50 kHz
• Gain: Gain error: ±0.5% (maximum); Gain drift: ±20 ppm/°C (maximum)
• Offset: Offset voltage: ±55 μV (typical); Offset drift: ±0.1 μV/°C (typical)
• Available gains: INA281A1, INA281B1: 20 V/V; INA281A2, INA281B2: 50 V/V; INA281A3, INA281B3: 100 V/V; INA281A4, INA281B4: 200 V/V; INA281A5, INA281B5: 500 V/V
• High bandwidth: 1.3 MHz
• Slew rate: 2.5 V/μs
• Quiescent current: 1.5 mA